Shadowman vs Chaos
Suggested by Sonic Chaos has a lot of forms at his disposal. You could make the case that his most powerful form is either Chaos 5 or Perfect Chaos. Either way Shadowman is too fast to lose this one. Not only is he skilled with a blast but he can move silently and with precision. Chaos will have a difficult time landing any kind of blow on him. Meanwhile Shadowman’s attacks will deal a lot of damage and the damage will quickly add up. There’s no way Chaos can endure the attacks long enough to land a counter. Shadowman wins.